WF extra info Flashcards
Scats rarely used as forensic evidence
(Trace, 2014)
Disadvantage of identifying species from hair morphology
Need reference samples for comparison
Bird feathers used to identify birds in bird strikes to learn behaviour and avoid them.
(Hoekenga, 2007)
Barbules and nodes (microscopic features) are most useful in identifying by observation.
(TRACE, 2014)
Can gain enough DNA from 2 feather barbs
(Speller, Nicholas and Young. 2011)
Advantages of feathers as forensic evidence
Little needed for DNA analysis
Some very distinctive so fast
Can identify where trade is occuring
Disadvantages of feathers as forensic evidence
Time and expense of DNA analysis
Need reference samples for DNA and morphology
Advantages of hair as forensic evidence
Can identify location - trafficking - palynomorphs, isotopes
Drugs can be detected
Disadvantages of hair as forensic evidence
DNA only with follicle
Need reference samples
Each plant genus has its own unique pollen grain morphology
(Marquez-Grant, N and Roberts, J. 2012)
Treeclimbing irons can link a person to egg collecting as they leave marks in trees.
(TRACE, 2014)
Advantages of eggs as forensic evidence
Fingerprints and DNA can be lifted
Equipment can link a suspect
Disadvantages of eggs as forensic evidence.
Difficult to ID from morphology alone
Need reference sequences for comparison
South Korea has largest market for deer antler products and 8 major pharmaceutical companies produce products derived from deer antler
(Robbins, C. 1997)
Mitochondrial DNA sequences such as cytochrome b are often favoured for DNA analysis as they show greater variation between closely related individuals than nuclear DNA
(Gunn, A. 2009)
Advantages of antlers as forensic evidence
If intact, can tell if naturally shed or removed
Velvet also suggests foreceful removal
Toolmarks can be identified
Disadvantages of antlers as forensic evidence
Tends to be sold in slices
Fraud makes DNA analysis complicated
Advantages of horns as forensic evidence
When intact, relatively easy to ID
Disadvantages of horns as forensic evidence
Diplomats not searched at airports
DNA may be present to ID offender due to force of removal
Raman Spectroscopy requires very little material and is therefore useful for identifying the provenance of carvings
(Gunn, A. 2009)
Advantages of ivory as forensic evidence
Radioisotope analysis
Morphology fairly distinctive
Disadvantages of ivory as forensic evidence
When carved, need specialist techniques
DNA must be taken from the mineral matrix
DNA must be taken from the mineral matrix and it is difficult to extract without denaturing the DNA
(Gunn, A. 2009)
. In 1990, a global ban on the trade in ivory was introduced by CITES and allowed some elephant populations to recover a little.
(Gunn, A. 2009)
2007, elephant ivory worth $850
(Gunn, A. 2009)
Combined weight of African elephant tusks is around 80kg
(Gunn, A. 2009)
Despite the ban on the trade, Africa is a country in which there is little aid for law enforcement and civil strife is high so the ban is not enforced here with much power.
(Gunn, A. 2009)
Bushmeat was originally considered beneficial as it demonstrated to locals the need for conservation, however, as populations and demand for bushmeat has grown, and profits have increased, these benefits are nowhere to be seen
(Gunn, A. 2009)
DNAboost generates a list of all the possible profiles based on the DNA available and then compares each of these profiles to profiles stored on the NDAD
(Gunn, A. 2009)
Advantages of bushmeat as forensic evidence
Can prosecute restaurant owner and supplier
Increased awareness of zoonotic diseases
Disadvantages of bushmeat as forensic evidence
Expensive to ID
Logging roads led to increased bushmeat as easier access to forests
(Karesh, W and Noble, E. 2009).
Dipstick test for bear bile takes 5 mins and can be used by customs officers as no specialist knowledge required. Detects albumin in skin, blood and liquid bile.
(Peppin et al. 2008)
HPLC shows that Asiatic black bear has lower concentration of TC than North American black bear and Polar bear.
(Lin, D et al. 1997)
Advantages of bear bile as forensic evidence.
Preliminary testing in the field
Disadvantages of bear bile as forensic evidence.
Accurate ID is time consuming and expensive
Morphologically identical to pigs and goats
RFLP needs large amounts of DNA and is often not possible to retrieve sufficient amounts of DNA from crime scenes. Another problem is that RFLP needs an intact sequence and this is not possible where DNA has undergone degradation
(Li, R. 2008)
Advantage of AFLP
Requires less DNA than RFLP and is more effective on degraded samples.
PCR first used in the diagnosis of sickle cell anaemia
(Li, R. 2008)
a man in Lincolnshire was fined almost £2000 for poisoning two buzzards by lacing a dead pheasant with carbofuran
(RSPB, 2013)
Farmers or gamekeepers poison keep animals off their land that they believe to be causing harm to their animals or crops, even if they are not legally deemed a pest species
(Gunn, A. 2009)
Advantages of musk deer oil as forensic evidence
Can be fairly reliably identified using GC-MS
Species can be identified using hair or DNA analysis
Disadvantages of musk deer oil as forensic evidence
Morphological features rarely present so expensive DNA analysis required.
Why is the medulla useful in species identification?
It varies greatly between species
What gives feathers their colour and distinctive patterns?
Pennaceous barbs
What has contributed to the illegal trade in antlers?
Traditional Chinese medicine Organised crime Internet Musk deer Increasing affluence
What country has the largest market for dear antler?
South Korea
When DNA analysis is used to identify a species, what is required?
A reference sequence for comparison
How may blood be used to identify a species?
Insert the blood of the animal to be identified into a host animal which will then produce anti(species) antibodies. A reference is needed however for this method
What is the advantage of Raman spectroscopy?
It requires very little material
Where are Ivor detection dogs being employed?
Kenyan airports
When did CITES instigate a global ban on elephant ivory?
1990
Why was bushmeat initially considered beneficial?
It showed locals the need for conservation
How do universal primers work to identify bushmeat?
CO1 sequences from all major eukaryotes groups aligned and conserved amino acid strings for shorter fragments (120-150bp) are observed
What animal has Ebola been linked to?
Chimpanzees
How have logging roads led to an increase in bushmeat?
Easier access to the depths of the forest for poachers
What can HPLC determine for bear bile?
The amount of TC present in a sample
What measures were included in the 2000 signing ceremony to combat trade in bear bile?
- Closure of worst bear farms
- Need license for farms
- No new licences issued
- AAF offer compensation to farmers and help finding new jobs
- Research into alternative medicines
How does RFLP work?
Restriction endonucleases create fragments of various lengths which are run through electrophoresis.
How does electrophoresis work?
DNA -ive so moves to +ive electrode. Shorter fragments travel further and agarose gel stained with ethidium bromide to fluoresce DNA. Banding compared to references.
What is a disadvantage of rflp?
Needs lots of DNA and no degradation
Problem with aflp?
Alleles of differing sizes may not be consistently amplified.
How can cases of poisoning be identified?
If many animals found dead close together.
If alive, measure levels of acetylcholinesterase using HPLC or GCMS, low levels indicate insecticide poisoning.
